IS does not close session when Grinder tests a service

I’m load-testing a IS service using The Grinder3, and I’m finding an annoying symptom: when I send the request using a browser (i.e. Mozilla), the session is opened and closed (I can follow it looking at the web-based IS Administration Statistics page: the session count does not increment), but when I use the grinder, the sessions are not closed. The session keeps up until it times out.

I have used
control.setDefaultHeaders( (NVPair(“Connection”, “close”),) )
but it does not change anything, and I have tried to proxy again the talk between the browser and IS, but I found no difference between the code I handcrafted and the one that the TCPFilter has generated.

The strange thing is that the connections are closed on the grinder machine (running netstat does not give any connection with the IS) but on the IS machine, netstat does return ‘TIME WAIT’.

So does anyone who knows what is happening here, or what should I do to make IS close these connections?

The IS is version 6.0.1, and it is running on a SunFire280 with Solaris 8, and the grinder machine is just a Debian 2.2 running Grinder3 beta14.

Dear Feng Sian,
I would like to know how to use Grinder to test the flow services of webMethods. Please guide me in detail how to use Grinder.

Thank you,